| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.hadoop.hdfs.qjournal.protocol; |
| |
| import java.io.IOException; |
| import java.net.URL; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.hdfs.DFSConfigKeys; |
| import org.apache.hadoop.hdfs.qjournal.client.QuorumJournalManager; |
| import org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos.GetEditLogManifestResponseProto; |
| import org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos.GetJournalStateResponseProto; |
| import org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos.NewEpochResponseProto; |
| import org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos.PrepareRecoveryResponseProto; |
| import org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos.SegmentStateProto; |
| import org.apache.hadoop.hdfs.qjournal.server.JournalNode; |
| import org.apache.hadoop.hdfs.server.namenode.JournalManager; |
| import org.apache.hadoop.hdfs.server.protocol.NamespaceInfo; |
| import org.apache.hadoop.security.KerberosInfo; |
| |
| /** |
| * Protocol used to communicate between {@link QuorumJournalManager} |
| * and each {@link JournalNode}. |
| * |
| * This is responsible for sending edits as well as coordinating |
| * recovery of the nodes. |
| */ |
| @KerberosInfo( |
| serverPrincipal = DFSConfigKeys.DFS_JOURNALNODE_USER_NAME_KEY, |
| clientPrincipal = DFSConfigKeys.DFS_NAMENODE_USER_NAME_KEY) |
| @InterfaceAudience.Private |
| public interface QJournalProtocol { |
| public static final long versionID = 1L; |
| |
| /** |
| * @return true if the given journal has been formatted and |
| * contains valid data. |
| */ |
| public boolean isFormatted(String journalId) throws IOException; |
| |
| /** |
| * Get the current state of the journal, including the most recent |
| * epoch number and the HTTP port. |
| */ |
| public GetJournalStateResponseProto getJournalState(String journalId) |
| throws IOException; |
| |
| /** |
| * Format the underlying storage for the given namespace. |
| */ |
| public void format(String journalId, |
| NamespaceInfo nsInfo) throws IOException; |
| |
| /** |
| * Begin a new epoch. See the HDFS-3077 design doc for details. |
| */ |
| public NewEpochResponseProto newEpoch(String journalId, |
| NamespaceInfo nsInfo, long epoch) throws IOException; |
| |
| /** |
| * Journal edit records. |
| * This message is sent by the active name-node to the JournalNodes |
| * to write edits to their local logs. |
| */ |
| public void journal(RequestInfo reqInfo, |
| long segmentTxId, |
| long firstTxnId, |
| int numTxns, |
| byte[] records) throws IOException; |
| |
| |
| /** |
| * Heartbeat. |
| * This is a no-op on the server, except that it verifies that the |
| * caller is in fact still the active writer, and provides up-to-date |
| * information on the most recently committed txid. |
| */ |
| public void heartbeat(RequestInfo reqInfo) throws IOException; |
| |
| /** |
| * Start writing to a new log segment on the JournalNode. |
| * Before calling this, one should finalize the previous segment |
| * using {@link #finalizeLogSegment(RequestInfo, long, long)}. |
| * |
| * @param txid the first txid in the new log |
| */ |
| public void startLogSegment(RequestInfo reqInfo, |
| long txid) throws IOException; |
| |
| /** |
| * Finalize the given log segment on the JournalNode. The segment |
| * is expected to be in-progress and starting at the given startTxId. |
| * |
| * @param startTxId the starting transaction ID of the log |
| * @param endTxId the expected last transaction in the given log |
| * @throws IOException if no such segment exists |
| */ |
| public void finalizeLogSegment(RequestInfo reqInfo, |
| long startTxId, long endTxId) throws IOException; |
| |
| /** |
| * @throws IOException |
| * @see JournalManager#purgeLogsOlderThan(long) |
| */ |
| public void purgeLogsOlderThan(RequestInfo requestInfo, long minTxIdToKeep) |
| throws IOException; |
| |
| /** |
| * @param jid the journal from which to enumerate edits |
| * @param sinceTxId the first transaction which the client cares about |
| * @return a list of edit log segments since the given transaction ID. |
| */ |
| public GetEditLogManifestResponseProto getEditLogManifest( |
| String jid, long sinceTxId) throws IOException; |
| |
| /** |
| * Begin the recovery process for a given segment. See the HDFS-3077 |
| * design document for details. |
| */ |
| public PrepareRecoveryResponseProto prepareRecovery(RequestInfo reqInfo, |
| long segmentTxId) throws IOException; |
| |
| /** |
| * Accept a proposed recovery for the given transaction ID. |
| */ |
| public void acceptRecovery(RequestInfo reqInfo, |
| SegmentStateProto stateToAccept, URL fromUrl) throws IOException; |
| } |